1. Field of the Invention
The present invention relates to medicinal compositions and more particularly refers to such compositions for tear replacement therapy having products of human lacrimal gland acinar epithelia, and more specifically, growth factors or cytokines, in particular, the transforming growth factor beta (TGF.beta.).
2. Background Information
Aqueous tear deficiency is a common condition that in its most severe form may be associated with disabling ocular irritation, and visual morbidity due to corneal epitheliopathy and/or ulceration. The conjunctival pathology of Sjogren's Syndrome (SS), the most severe type of aqueous tear deficiency, consists of abnormal terminal differentiation with significantly reduced bulbar goblet cell densities (Pflugfelder, S. C. et al. Ophthalmology 1990;97:985-991), decreased expression of mucins by the superficial epithelium (Table I)(Pflugfelder, S. C. et al. 1994 ARVO abstracts. Invest. Ophthalmol. Vis. Sci. 1994; 34: 1692)), and aberrant expression of immune activation markers (HLA Class II antigens and ICAM I) and interleukin 6 (IL-6) (Jones, D. T. et al. Invest. Ophthalmol. Vis. Sci. (in press)).
TABLE I __________________________________________________________________________ Results of Immunohistochemical Staining of Bulbar Conjunctival Epithelial Cells on Impression Cytology Specimens using Mucin-Specific Antibody L6 Group Temporal Conjuctiva (% +) Inferior Conjuctiva (% +) __________________________________________________________________________ Sjogren Syndrome (SS) ATD 18.2 18.2 Non Sjogren Syndrome ATD 66.7 88.9 inflammatory MGD 77.8 88.9 Atrophic MGD 77.8 100 Control 100 100 SS vs Inflam. MGD p = 0.022 SS vs non SS ATD p = 0.005 SS vs Atrophic MGD p = 0.022 SS vs Inflam. MGD p = 0.005 SS vs control p = 0.001 SS vs Atrophic MGD p = 0.001 SS vs control p = 0.001 __________________________________________________________________________ ATD = aqueous tear deficiency, MGD = meibomian gland disease
At the present time, biological activity of tears on the health and differentiation of the ocular surface epithelia has not been evaluated. Clinical signs and ocular surface pathologic changes in patients with aqueous tear deficiency suggest that the tears may have more than a lubricating role for the ocular surface. One of the most specific clinical signs of severe aqueous tear deficiency is staining of the conjunctival and/or cornea with the diagnostic dye rose-bengal. Recently reported experimental evidence suggests that rose-bengal staining of the ocular surface epithelia may result from lack of cell coating by normal tear constituents, predominantly tear mucins (Feenstra, R. P. and Tseng, S. C. G. Arch. Ophthalmol. 1992;110:984-993). Mucin-producing goblet cells and production of cell-membrane associated mucins by the superficial stratified epithelia are markers of terminal differentiation in the normal human conjunctiva. A marked reduction in expression of both types of conjunctival mucin has been detected in the conjunctival epithelia of Sjogren's Syndrome patients (Pflugfelder, S. C. et al. Ophthalmology 1990;97:985-991. Pflugfelder, S. C. et al., 1994 ARVO abstracts Invest. Ophthalmol. Vis. Sci. 1994; 34: 1692).
Although this may be due in part to mechanical trauma related to the reduced preocular tear film, it may also represent abnormal terminal differentiation due to lack of biologically active tear constituents. At the present time, epidermal growth factor (EGF) is the only cytokine that has been detected in human tears (van Seten, G. B. et al. Graeffe's Arch. Clin. Exp. Ophthalmol. 1989;227: 184-187). Reduced tear EGF concentrations have been reported in one patient with aqueous tear deficiency (van Seten, G. B. et al. Curr. Eye Res. 1991; 10:523-527; however, the biologic activity of tear EGF has not been evaluated.
Tear secretion by the human lacrimal gland is influenced by neurotransmitters and hormones (Dartt, D. Curr. Eye Res. 1989;8:619-636; Sullivan, D. A. The Neuro Endocrine-immune Network S. Freier, Editor. Boca Raton, Fla. 1990 CRC Press, pp 199-238). Jordan and Baum have reported that the majority of tear secretion is reflexive, resulting from sensory stimulation of the lids and ocular surface (Jordan, A. and Baum, J. Ophthalmology 1980;87:920-930). A marked reduction in neural-stimulated tear secretion is an early clinical sign in Sjogren's Syndrome (Tsubota, K. Am. J. Ophthalmol. 1991; 111: 106-108), but the clinical consequences of reduced neural-stimulated tears have not been established.
We recently discovered that the pathologic changes associated with Sjogren's Syndrome may be due in part to reduced concentrations of cytokines produced by the lacrimal gland and secreted into the tears that are essential for normal health and differentiation of the ocular surface epithelia. Based on its ability to induce differentiation of intestinal mucosa (Kurokowa, M. et al., Biochem. Biophys. Comm. 1987; 142:775-782), and corneal epithelia (Kruse, F. E. and Tseng. S. C. G. Invest. Ophthalmol. Vis. Sci. 1993;34: 1963-1976), and its ability to down regulate HLA Class II antigen and IL-6 expression (Lucas, C. et al. Ciba Foundation 1991; 157:98-114), we hypothesized that transforming growth factor beta (TGF.beta.) may be one of the biologically essential tear cytokines. Recently, TGF has been reported to be produced by mammary gland acini (Maier, R. et al. Mol. Cell. Endocrinol. 1991;82: 192-198) and secreted into milk.
TGF.beta. is a multi-functional biologically essential cytokine. TGF.beta. has a spectrum of biologic activity and has been reported to induce differentiation and inhibit proliferation of mucosal epithelia, including rabbit corneal epithelia (Kurokowa, M. et al. Biochem. Biophys. Comm. 1987; 142:775-782; Kruse, F. E. and Tseng, S. C. G. Invest. Ophthalmol. Vis. Sci. 1993;34: 1963-1976). TGF.beta. has also been reported to stimulate synthesis of extra cellular matrix components and has been shown to induce these effects on corneal stromal fibroblasts (Ohji, M. et al. Curr. Eye. Res. 1993;12:703-709). Finally, TGF.beta. has immunosuppressive activity that includes inhibition of T-cell proliferation, down regulation of expression of inflammatory cytokines such as IL-6 and immune activation markers such as HLA class II antigens (Lucas, C. et al. Ciba Foundation 1991; 157:98-114).
At the present time, commercially available artificial tear replacements are composed of synthetic polymers, buffers, and electrolytes in an aqueous solution. Examples of such solutions include "BION" (Alcon Laboratories, Fort Worth, Tex.) and "REFRESH PLUS" (Allersan, Irvine, Calif.). Major components of commercially available artificial tear replacement solutions, Ophthalmic lubricants which protect the eye from drying, and ocular decongestants, are listed in TABLES II, III, and IV, respectively. These solutions contain no biologically active components to modulate the health and differentiation of ocular surface epithelia. Tear replacement therapies containing biologically active components could potentially reverse pathologic ocular surface epithelial changes, and would present a great advance in treatment of severe aqueous tear deficiency states.
TABLE II __________________________________________________________________________ ARTIFICIAL TEAR PREPARATIONS MAJOR COMPONENT CONCENTRATION TRADENAME PRESERVATIVE/EDTA __________________________________________________________________________ Carboxy methycellulose 0.5% Cellufresh None 1% Celluvisc None Hydroxyethyl cellulose Lyteers Benzalkonium Cl + EDTA TearGard Sorbic Acid + EDTA Hydroxyethyl cellulose + Neo-Tears Thimerosal + EDTA Polyvinyl Alcohol Pydroxyethyl cellulose + Adsorbotear Thimerosal + EDTA Povidone Hydroxypropyl Cellulose Lacrisert (Biode- None gradable insert) Hydroxypropyl Methylcellulose 0.5% Isopto Plain Benzalkonium Cl Isopto Tears Benzalkonium Cl Tearisol Benzalkonium Cl + EDTA 1% Isopto Alkaline Benzalkonium Cl Ultra Tears Benzalkonium Cl Hydroxypropyl Methylcellulose + Tears Naturale Benzalkonium Cl + EDTA Dextran 70 Tears Naturale II Polyquad Tears Naturale Free None Hydroxypropyl Methylcellulose + Lacril Chlorobutanol + Gelatin A Polysorbate 80 Methylcellulos 1% Murocel Methyl- + Propylparabens Polyvinyl Alcohol 1.4% Akwa Tears Benzalkonium Cl + EDTA Just Tears Benzalkonium Cl + EDTA Liquifilm Tears Chlorobutanol 3% Liquifilm Forte Thimerosal + EDTA Polyvinyl Alcohol + 1% Hypotears Benzalkonium Cl + EDTA PEG-400 + Dextose Hypotears PF EDTA Polyvinyl Alcohol + 1.4% Murine Benzalkonium Cl + EDTA Povidone 0.6% Refresh None Tears Plus Chlorobutanol __________________________________________________________________________
TABLE III ______________________________________ OPHTHALMIC LUBRICANTS TRADE NAME COMPOSITION ______________________________________ AKWA Tears Ointment (Akorn) Sterile ointment containing white petrolatum, liquid lanolin, and mineral oil. Duolube (Bausch & Lomb) Sterile ointment containing white petrolatum and mineral oil. Duratears Naturale (Alcon) Sterile ointment containing white petrolatum, liquid lanolin, and mineral oil. HypoTears (Iolab) Sterile ointment containing white petrolatum and light mineral oil. Lacri-Lube S.O.P. (Allergan) Sterile ointment containing 42.5% mineral oil, 55% white petrolatum, lanolin alcohol, and chlorobutanol. Refresh P.M. (Allergan) Sterile ointment containing 41.5% mineral oil, 55% white petrolatum, petrolatum, and lanolin alcohol. ______________________________________
TABLE IV __________________________________________________________________________ DRUG TRADE NAME ADDITIONAL COMPONENTS __________________________________________________________________________ OCULAR DECONGESTANTS Naphazoline AK-Con* Benzalkonium Cl + edetate disodium Hydrochloride Albalon* Benzalkonium Cl + edetate disodium Clear Eyes Benzalkonium Cl + edetate disodium Degest 2 Benzalkonium Cl + edetate disodium Naphcon* Benzalkonium Cl + edetate disodium Opcon* Benzalkonium Cl + edetate disodium Vasoclear Benzalkonium Cl + edetate disodium Vasocon Regular* Phenylmercuric acetate Phenylephrine AK-Nefrin Benzalkonium Cl + edetate disodium Hydrochloride Efricel Benzalkonium Cl + edetate disodium Eye Cool Thimerosal + edetate disodium Isopto Frin Benzalkonium Cl + edetate disodium Prefin Liquifilm Benzalkonium Cl + edetate disodium Relief -- Tear-Efrin Benzalkonium Cl + edetate disodium Velva-Kleen Thimerosal + edetate disodium Tetrahydrozoline Collyrium Benzalkonium Cl + edetate disodium Hydrochloride Murine Plus Benzalkonium Cl + edetate disodium Soothe* Benzalkonium Cl + edetate disodium Tetracon Benzalkonium Cl + edetate disodium Visine Benzalkonium Cl + edetate disodium DECONGESTANT/ASTRINGENT COMBINATIONS Naphazoline Clear Eyes ACR Benzalkonium Cl + edetate disodium Hydrochloride (Allergy/Cold plus Zinc Sulfate Relief) Phenylephrine Prefrin-Z Thimerosal Hydrochloride Zincfrin Benzalkonium Cl plus Zinc Sulfate Tetrahydrozoline Visine A.C. Benzalkonium Cl + edetate disodium plus Zinc Sulfate __________________________________________________________________________ *Prescription medication